| Citation: | Clemens V. Ullmann, Magret Damaschke, Stephen P. Hesselbo, Mengjie Jiang, Kathryn Lawrence, Melanie J. Leng, Emanuela Mattioli, Jérold Bancalin, Kevin N. Page, Nour Pudal, Micha Ruhl, Ricardo L. Silva. An Integrated Biostratigraphy and Chemostratigraphy for the Dawn of the Jurassic (the Hettangian Stage in the Cheshire Basin, UK). Journal of Earth Science, 2026, 37(3): 945-967. doi: 10.1007/s12583-025-0205-6 |
Highly resolved Earth System reconstructions of the Earliest Jurassic are hampered by complexities of existing reference sections. Here, an integrated stratigraphy of two core records is constructed, representing the expanded Hettangian sequence of the Cheshire Basin, UK. The combined record is based on ammonite and calcareous nannofossil biostratigraphy, organic carbon isotope ratios, and bulk rock chemical properties of legacy core material (Wilkesley) and Prees 2C, cored in 2020. Combination of ammonite records of these cores allows for substantial reductions in the uncertainties of ammonite zonal and subzonal boundaries. The new organic carbon isotope chemostratigraphy for the Hettangian of the Cheshire Basin improves temporal resolution compared to other published records, in particular for the Tilmanni and Planorbis zones. The limited occurrence of organic matter enrichment intervals associated with negative organic carbon isotope spikes in the Cheshire Basin allows for the identification of minor drifts throughout the Hettangian and into the Sinemurian which are likely of global significance. Organic carbon and macrofossil carbonate carbon isotope ratios largely follow the same trends in the Hettangian, but exhibit contrasting changes in the early Liasicus Zone, commensurate with a decrease in the isotopic difference of both records of ca. 2‰.
| Arthurton, R. S., 1980. Rhythmic Sedimentary Sequences in the Triassic Keuper Marl (Mercia Mudstone Group) of Cheshire, Northwest England. Geological Journal, 15(1): 43–58. https://doi.org/10.1002/gj.3350150106 |
| Bachan, A., van de Schootbrugge, B., Fiebig, J., et al., 2012. Carbon Cycle Dynamics Following the End-Triassic Mass Extinction: Constraints from Paired δ13Ccarb and δ13Corg Records. Geochemistry, Geophysics, Geosystems, 13(9): 2012GC004150. https://doi.org/10.1029/2012gc004150 |
| Barron, A. J. M., Lott, G. K., et al., 2012. Stratigraphical Framework for the Middle Jurassic Strata of Great Britain and the Adjoining Continental Shelf. British Geological Survey Research Report, RR/11/06. 187 |
| Bartolini, A., Guex, J., Spangenberg, J. E., et al., 2012. Disentangling the Hettangian Carbon Isotope Record: Implications for the Aftermath of the End-Triassic Mass Extinction. Geochemistry, Geophysics, Geosystems, 13: 2011GC003807. https://doi.org/10.1029/2011gc003807 |
| Beith, S. J., Fox, C. P., Marshall, J. E. A., et al., 2021. Recurring Photic Zone Euxinia in the Northwest Tethys Impinged End-Triassic Extinction Recovery. Palaeogeography, Palaeoclimatology, Palaeoecology, 584: 110680. https://doi.org/10.1016/j.palaeo.2021.110680 |
| Blackburn, T. J., Olsen, P. E., Bowring, S. A., et al., 2013. Zircon U-Pb Geochronology Links the End-Triassic Extinction with the Central Atlantic Magmatic Province. Science, 340(6135): 941–945. https://doi.org/10.1126/science.1234204 |
| Bloos, G., Page, K. N., 2000. The Basal Jurassic Ammonite Succession in the North-West European Province: Review and New Results. GeoResearch Forum, 6: 27–40 |
| Bloos, G., Page, K. N., 2002. Global Stratotype Section and Point for Base of the Sinemurian Stage (Lower Jurassic). Episodes, 25(1): 22–28. https://doi.org/10.18814/epiiugs/2002/v25i1/003 |
| Boomer, I., Copestake, P., Raine, R., et al., 2021. Stratigraphy, Palaeoenvironments and Geochemistry across the Triassic–Jurassic Boundary Transition at Carnduff, County Antrim, Northern Ireland. Proceedings of the Geologists' Association, 132(6): 667–687. https://doi.org/10.1016/j.pgeola.2020.05.004 |
| Bourquin, S., Bercovici, A., López-Gómez, J., et al., 2011. The Permian–Triassic Transition and the Onset of Mesozoic Sedimentation at the Northwestern Peri-Tethyan Domain Scale: Palaeogeographic Maps and Geodynamic Implications. Palaeogeography, Palaeoclimatology, Palaeoecology, 299(1/2): 265–280. https://doi.org/10.1016/j.palaeo.2010.11.007 |
| Bown, P. R., 1987. Taxonomy, Evolution, and Biostratigraphy of Late Triassic–Early Jurassic Calcareous Nannofossils. Special Papers in Palaeontology, 38: 1–118 |
| Bown, P. R., Cooper, M. K. E., 1998. Jurassic. In: Bown, P. R., ed., Calcareous Nannofossils Biostratigraphy. British Micropalaeon- tological Society Publication Series, Kluver Academic Publishers, Cambridge. 34–85 |
| Chadwick, R. A., 1997. Fault Analysis of the Cheshire Basin, NW England. Geological Society, London, Special Publications, 124(1): 297–313. https://doi.org/10.1144/gsl.sp.1997.124.01.18 |
| Clémence, M. E., Bartolini, A., Gardin, S., et al., 2010. Early Hettangian Benthic-Planktonic Coupling at Doniford (SW England) Palaeoenvironmental Implications for the Aftermath of the End-Triassic Crisis. Palaeogeography, Palaeoclimatology, Palaeoecology, 295(1/2): 102–115. https://doi.org/10.1016/j.palaeo.2010.05.021 |
| Copestake, P., Johnson, B., 2013. Lower Jurassic Foraminifera from the Llanbedr (Mochras Farm) Borehole, North Wales, UK. Monographs of the Palaeontographical Society, 167(641): 1–403. https://doi.org/10.1080/02693445.2013.11963952 |
| Dal Corso, J., Marzoli, A., Tateo, F., et al., 2014. The Dawn of CAMP Volcanism and Its Bearing on the End-Triassic Carbon Cycle Disruption. Journal of the Geological Society, 171(2): 153–164. https://doi.org/10.1144/jgs2013-063 |
| Damborenea, S. E., Echevarría, J., Ros-Franch, S., 2017. Biotic Recovery after the End-Triassic Extinction Event: Evidence from Marine Bivalves of the Neuquén Basin, Argentina. Palaeogeography, Palaeoclimatology, Palaeoecology, 487: 93–104. https://doi.org/10.1016/j.palaeo.2017.08.025 |
| Davies, J. H. F. L., Marzoli, A., Bertrand, H., et al., 2017. End-Triassic Mass Extinction Started by Intrusive CAMP Activity. Nature Communications, 8: 15596. https://doi.org/10.1038/ncomms15596 |
| Deenen, M. H. L., Krijgsman, W., Ruhl, M., 2011. The Quest for Chron E23r at Partridge Island, Bay of Fundy, Canada: CAMP Emplacement Postdates the End-Triassic Extinction Event at the North American Craton. Canadian Journal of Earth Sciences, 48(8): 1282–1291. https://doi.org/10.1139/e11-015 |
| Deenen, M. H. L., Ruhl, M., Bonis, N. R., et al., 2010. A New Chronology for the End-Triassic Mass Extinction. Earth and Planetary Science Letters, 291(1/2/3/4): 113–125. https://doi.org/10.1016/j.epsl.2010.01.003 |
| Donovan, D. T., 1966. The Hettangian Ammonites from the Wilkesley Borehole. In: Poole, E. G., Whiteman, A. J., 1966. Geology of the Country around Nantwich and Whitchurch. Memoirs of the Geological Survey of Great Britain, Her Majesty's Stationery Office |
| Evans, D. J., Rees, J. G., Holloway, S., 1993. The Permian to Jurassic Stratigraphy and Structural Evolution of the Central Cheshire Basin. Journal of the Geological Society, 150(5): 857–870. https://doi.org/10.1144/gsjgs.150.5.0857 |
| Fendley, I. M., Frieling, J., Mather, T. A., et al., 2024. Early Jurassic Large Igneous Province Carbon Emissions Constrained by Sedimentary Mercury. Nature Geoscience, 17(3): 241–248. https://doi.org/10.1038/s41561-024-01378-5 |
| Fox, C. P., Cui, X. Q., Whiteside, J. H., et al., 2020. Molecular and Isotopic Evidence Reveals the End-Triassic Carbon Isotope Excursion is not from Massive Exogenous Light Carbon. Proceedings of the National Academy of Sciences of the United States of America, 117(48): 30171–30178. https://doi.org/10.1073/pnas.1917661117 |
| Frizon de Lamotte, D., Fourdan, B., Leleu, S., et al., 2015. Style of Rifting and the Stages of Pangea Breakup. Tectonics, 34(5): 1009–1029. https://doi.org/10.1002/2014tc003760 |
| Fujisaki, W., Matsui, Y., Asanuma, H., et al., 2018. Global Perturbations of Carbon Cycle during the Triassic–Jurassic Transition Recorded in the Mid-Panthalassa. Earth and Planetary Science Letters, 500: 105–116. https://doi.org/10.1016/j.epsl.2018.07.026 |
| Gallois, R., 2000. The Stratigraphy of the Kimmeridge Clay Formation (Upper Jurassic) in the RGGE Project Boreholes at Swanworth Quarry and Metherhills, South Dorset. Proceedings of the Geologists' Association, 111(3): 265–280. https://doi.org/10.1016/S0016-7878(00)80019-X |
| Ge, Y. Z., Shi, M., Steuber, T., et al., 2018. Environmental Change during the Triassic–Jurassic Boundary Interval of an Equatorial Carbonate Platform: Sedimentology and Chemostratigraphy of the Ghalilah Formation, United Arab Emirates. Palaeogeography, Palaeoclimatology, Palaeoecology, 502: 86–103. https://doi.org/10.1016/j.palaeo.2018.04.026 |
| Guex, J., Schoene, B., Bartolini, A., et al., 2012. Geochronological Constraints on Post-Extinction Recovery of the Ammonoids and Carbon Cycle Perturbations during the Early Jurassic. Palaeogeography, Palaeoclimatology, Palaeoecology, 346: 1–11. https://doi.org/10.1016/j.palaeo.2012.04.030 |
| Hallam, A., 1997. Recovery of the Marine Fauna in Europe after the End-Triassic and Early Toarcian Mass Extinctions. Geological Society, London, Special Publications, 102(1): 231–236. https://doi.org/10.1144/gsl.sp.1996.001.01.16 |
| Hatfield, R. G., Woods, A., Lehmann, S. B., et al., 2020. Stratigraphic Correlation and Splice Generation for Sediments Recovered from a Large-Lake Drilling Project: An Example from Lake Junín, Peru. Journal of Paleolimnology, 63(1): 83–100. https://doi.org/10.1007/s10933-019-00098-w |
| Hesselbo, S. P., Al-Suwaidi, A., Baker, S. J., et al., 2023. Initial Results of Coring at Prees, Cheshire Basin, UK (ICDP JET Project): Towards an Integrated Stratigraphy, Timescale, and Earth System Understanding for the Early Jurassic. Scientific Drilling, 32: 1–25. https://doi.org/10.5194/sd-32-1-2023 |
| Hesselbo, S. P., Jenkyns, H. C., Duarte, L. V., et al., 2007. Carbon-Isotope Record of the Early Jurassic (Toarcian) Oceanic Anoxic Event from Fossil Wood and Marine Carbonate (Lusitanian Basin, Portugal). Earth and Planetary Science Letters, 253(3/4): 455–470. https://doi.org/10.1016/j.epsl.2006.11.009 |
| Hesselbo, S. P., Korte, C., Ullmann, C. V., et al., 2020a. Carbon and Oxygen Isotope Records from the Southern Eurasian Seaway Following the Triassic-Jurassic Boundary: Parallel Long-Term Enhanced Carbon Burial and Seawater Warming. Earth-Science Reviews, 203: 103131. https://doi.org/10.1016/j.earscirev.2020.103131 |
| Hesselbo, S. P., Ogg, J. G., Ruhl, M., et al., 2020b. The Jurassic Period. Geologic Time Scale 2020. Elsevier, Amsterdam. 955–1021. https://doi.org/10.1016/b978-0-12-824360-2.00026-7 |
| Hesselbo, S. P., Robinson, S. A., Surlyk, F., 2004. Sea-Level Change and Facies Development across Potential Triassic-Jurassic Boundary Horizons, SW Britain. Journal of the Geological Society, 161(3): 365–379. https://doi.org/10.1144/0016-764903-033 |
| Hesselbo, S. P., Robinson, S. A., Surlyk, F., et al., 2002. Terrestrial and Marine Extinction at the Triassic-Jurassic Boundary Synchronized with Major Carbon-Cycle Perturbation: A Link to Initiation of Massive Volcanism. Geology, 30(3): 251. https://doi.org/10.1130/0091-7613(2002)0300251:tameat>2.0.co;2 doi: 10.1130/0091-7613(2002)0300251:tameat>2.0.co;2 |
| Hillebrandt, A. V., Krystyn, L., Kürschner, W. M., et al., 2013. The Global Stratotype Sections and Point (GSSP) for the Base of the Jurassic System at Kuhjoch (Karwendel Mountains, Northern Calcareous Alps, Tyrol, Austria). Episodes, 36(3): 162–198. https://doi.org/10.18814/epiiugs/2013/v36i3/001 |
| Hinga, K. R., Arthur, M. A., Pilson, M. E. Q., et al., 1994. Carbon Isotope Fractionation by Marine Phytoplankton in Culture: The Effects of CO2 Concentration, pH, Temperature, and Species. Global Biogeochemical Cycles, 8(1): 91–102. https://doi.org/10.1029/93gb03393 |
| Hüsing, S. K., Beniest, A., van der Boon, A., et al., 2014. Astronomically-Calibrated Magnetostratigraphy of the Lower Jurassic Marine Successions at St. Audrie's Bay and East Quantoxhead (Hettangian–Sinemurian; Somerset, UK). Palaeogeography, Palaeoclimatology, Palaeoecology, 403: 43–56. https://doi.org/10.1016/j.palaeo.2014.03.022 |
| Jeram, A. J., Simms, M. J., Hesselbo, S. P., et al., 2021. Carbon Isotopes, Ammonites and Earthquakes: Key Triassic-Jurassic Boundary Events in the Coastal Sections of South-East County Antrim, Northern Ireland, UK. Proceedings of the Geologists' Association, 132(6): 702–725. https://doi.org/10.1016/j.pgeola.2021.10.004 |
| Jones, D. G., Morton, A. C., Leng, M. J., et al., 1996. Chapter 4: Provenance of the Basin Fill. In: Plant, J. A., Jones, D. G., Haslam, H. W., eds., Basin Evolution, Fluid Movement and Mineral Resources in a Permo-Triassic Rift Setting: The Cheshire Basin. British Geological Survey, Technical Report, Abingdon |
| Kiessling, W., Aberhan, M., Brenneis, B., et al., 2007. Extinction Trajectories of Benthic Organisms across the Triassic–Jurassic Boundary. Palaeogeography, Palaeoclimatology, Palaeoecology, 244(1/2/3/4): 201–222. https://doi.org/10.1016/j.palaeo.2006.06.029 |
| Korte, C., Hesselbo, S. P., Jenkyns, H. C., et al., 2009. Palaeoenvironmental Significance of Carbon- and Oxygen-Isotope Stratigraphy of Marine Triassic-Jurassic Boundary Sections in SW Britain. Journal of the Geological Society, 166(3): 431–445. https://doi.org/10.1144/0016-76492007-177 |
|
Korte, C., Ruhl, M., Pálfy, J., et al., 2018. Chemostratigraphy across the Triassic–Jurassic Boundary. In: Chemostratigraphy across Major Chronological Boundaries. Geophysical Monograph Series (240). AGU Publications, Washington D. C. 1–49. |
| Kump, L. R., Arthur, M. A., 1999. Interpreting Carbon-Isotope Excursions: Carbonates and Organic Matter. Chemical Geology, 161(1/2/3): 181–198. https://doi.org/10.1016/S0009-2541(99)00086-8 |
| Lindström, S., van de Schootbrugge, B., Hansen, K. H., et al., 2017. A New Correlation of Triassic–Jurassic Boundary Successions in NW Europe, Nevada and Peru, and the Central Atlantic Magmatic Province: A Time-Line for the End-Triassic Mass Extinction. Palaeogeography, Palaeoclimatology, Palaeoecology, 478: 80–102. https://doi.org/10.1016/j.palaeo.2016.12.025 |
| Lucas, S. G., Tanner, L. H., 2015. End-Triassic Nonmarine Biotic Events. Journal of Palaeogeography, 4(4): 331–348. https://doi.org/10.1016/j.jop.2015.08.010 |
| McRoberts, C. A., Ward, P. D., Hesselbo, S., 2007. A Proposal for the Base Hettangian Stage (= Base Jurassic System) GSSP at New York Canyon (Nevada, USA) Using Carbon Isotopes. International Subcommission on Jurassic Stratigraphy Newsletter, 34(1): 43–49 |
|
Menini, A., Mattioli, E., Hesselbo, S. P., et al., 2021. Primary v. Carbonate Production in the Toarcian, a Case Study from the Llanbedr (Mochras Farm) Borehole, Wales. In: Reolid, M., Duarte, L. V., Mattioli, E., et al., eds., Carbon Cycle and Ecosystem Response to the Jenkyns Event in the Early Toarcian (Jurassic). Geological Society, London, Special Publications, 514. |
| Morgans-Bell, H. S., Coe, A. L., Hesselbo, S. P., et al., 2001. Integrated Stratigraphy of the Kimmeridge Clay Formation (Upper Jurassic) Based on Exposures and Boreholes in South Dorset, UK. Geological Magazine, 138(5): 511–539. https://doi.org/10.1017/s0016756801005738 |
| Naylor, H., Turner, P., Vaughan, D. J., et al., 1989. Genetic Studies of Red Bed Mineralization in the Triassic of the Cheshire Basin, Northwest England. Journal of the Geological Society, 146(4): 685–699. https://doi.org/10.1144/gsjgs.146.4.0685 |
| Newell, A. J., 2018. Rifts, Rivers and Climate Recovery: A New Model for the Triassic of England. Proceedings of the Geologists' Association, 129(3): 352–371. https://doi.org/10.1016/j.pgeola.2017.04.001 |
|
Pálfy, J., 2003. Volcanism of the Central Atlantic Magmatic Province as a Potential Driving Force in the End-Triassic Mass Extinction. The Central Atlantic Magmatic Province: Insights from Fragments of Pangea. American Geophysical Union, Washington, D. C. 255–267. |
| Paris, G., Beaumont, V., Bartolini, A., et al., 2010. Nitrogen Isotope Record of a Perturbed Paleoecosystem in the Aftermath of the End-Triassic Crisis, Doniford Section, SW England. Geochemistry, Geophysics, Geosystems, 11(8): 2010GC003161. https://doi.org/10.1029/2010gc003161 |
| Paulsen, M., Thibault, N., 2023. On the Occurrence of Rare Nannoliths (Calcareous Nannofossils) in the Early Jurassic and Their Implications for the End-Triassic Mass Extinction. Papers in Palaeontology, 9(2): e1489. https://doi.org/10.1002/spp2.1489 |
| Paulsen, M., Thibault, N., Fraguas, Á., 2023. A Revised Calcareous Nannofossil Biozonation for the Lower Jurassic (Hettangian–Lower Pliensbachian) of NW Europe. Lethaia, 56(3): 1–20. https://doi.org/10.18261/let.56.3.4 |
| Penn, I. E., 1987. Geophysical Logs in the Stratigraphy of Wales and Adjacent Offshore and Onshore Areas. Proceedings of the Geologists' Association, 98(4): 275–314. https://doi.org/10.1016/S0016-7878(87)80072-X |
| Peti, L., Thibault, N., 2017. Abundance and Size Changes in the Calcareous Nannofossil Schizosphaerella: Relation to Sea-Level, the Carbonate Factory and Palaeoenvironmental Change from the Sinemurian to Earliest Toarcian of the Paris Basin. Palaeogeography, Palaeoclimatology, Palaeoecology, 485: 271–282. https://doi.org/10.1016/j.palaeo.2017.06.019 |
| Peti, L., Thibault, N., Korte, C., et al., 2021. Environmental Drivers of Size Changes in Lower Jurassic Schizosphaerella Spp. Marine Micropaleontology, 168: 102053. https://doi.org/10.1016/j.marmicro.2021.102053 |
| Poole, E. G., Whiteman, A. J., 1966. Geology of the Country around Nantwich and Whitchurch. Memoirs of the Geological Survey of Great Britain, Her Majesty's Stationery Office |
| Raup, D. M., Sepkoski, J. J. Jr., 1982. Mass Extinctions in the Marine Fossil Record. Science, 215(4539): 1501–1503. https://doi.org/10.1126/science.215.4539.1501 |
| Ruhl, M., Deenen, M. H. L., Abels, H. A., et al., 2010. Astronomical Constraints on the Duration of the Early Jurassic Hettangian Stage and Recovery Rates Following the End-Triassic Mass Extinction (St Audrie's Bay/East Quantoxhead, UK). Earth and Planetary Science Letters, 295(1/2): 262–276. https://doi.org/10.1016/j.epsl.2010.04.008 |
| Ruhl, M., Hesselbo, S. P., Al-Suwaidi, A., et al., 2020. On the Onset of Central Atlantic Magmatic Province (CAMP) Volcanism and Environmental and Carbon-Cycle Change at the Triassic-Jurassic Transition (Neuquén Basin, Argentina). Earth-Science Reviews, 208: 103229. https://doi.org/10.1016/j.earscirev.2020.103229 |
| Ruhl, M., Hesselbo, S. P., Hinnov, L., et al., 2016. Astronomical Constraints on the Duration of the Early Jurassic Pliensbachian Stage and Global Climatic Fluctuations. Earth and Planetary Science Letters, 455: 149–165. https://doi.org/10.1016/j.epsl.2016.08.038 |
| Ruhl, M., Kürschner, W. M., Krystyn, L., 2009. Triassic–Jurassic Organic Carbon Isotope Stratigraphy of Key Sections in the Western Tethys Realm (Austria). Earth and Planetary Science Letters, 281(3/4): 169–187. https://doi.org/10.1016/j.epsl.2009.02.020 |
| Schaltegger, U., Guex, J., Bartolini, A., et al., 2008. Precise U-Pb Age Constraints for End-Triassic Mass Extinction, Its Correlation to Volcanism and Hettangian Post-Extinction Recovery. Earth and Planetary Science Letters, 267(1/2): 266–275. https://doi.org/10.1016/j.epsl.2007.11.031 |
| Schoene, B., Guex, J., Bartolini, A., et al., 2010. Correlating the End-Triassic Mass Extinction and Flood Basalt Volcanism at the 100 ka Level. Geology, 38(5): 387–390. https://doi.org/10.1130/g30683.1 |
| Schöllhorn, I., Adatte, T., Van de Schootbrugge, B., et al., 2020. Climate and Environmental Response to the Break-up of Pangea during the Early Jurassic (Hettangian-Pliensbachian); The Dorset Coast (UK) Revisited. Global and Planetary Change, 185: 103096. https://doi.org/10.1016/j.gloplacha.2019.103096 |
| Storm, M. S., Hesselbo, S. P., Jenkyns, H. C., et al., 2020. Orbital Pacing and Secular Evolution of the Early Jurassic Carbon Cycle. Proceedings of the National Academy of Sciences of the United States of America, 117(8): 3974–3982. https://doi.org/10.1073/pnas.1912094117 |
| Suan, G., Mattioli, E., Pittet, B., et al., 2010. Secular Environmental Precursors to Early Toarcian (Jurassic) Extreme Climate Changes. Earth and Planetary Science Letters, 290(3/4): 448–458. https://doi.org/10.1016/j.epsl.2009.12.047 |
| Suan, G., van de Schootbrugge, B., Adatte, T., et al., 2015. Calibrating the Magnitude of the Toarcian Carbon Cycle Perturbation. Paleoceanography, 30(5): 495–509. https://doi.org/10.1002/2014pa002758 |
| Szeląg-Wasielewska, E., Pajchrowska, M., Mądrecka, B., et al., 2018. Seasonal Variation of the Calcifying Green Alga Phacotus Lenticularis (Ehrenb.) Stein in Water Bodies under Human Influence (Mid-Western Poland). Limnological Review, 18(2): 83–89. https://doi.org/10.2478/limre-2018-0009 |
| Tada, R., Irino, T., Ikehara, K., et al., 2018. High-Resolution and High-Precision Correlation of Dark and Light Layers in the Quaternary Hemipelagic Sediments of the Japan Sea Recovered during IODP Expedition 346. Progress in Earth and Planetary Science, 5: 19. https://doi.org/10.1186/s40645-018-0167-8 |
| Thomas, J. B., Marshall, J., Mann, A. L., et al., 1993. Dinosteranes (4, 23, 24-Trimethylsteranes) and Other Biological Markers in Dinoglagellate-Rich Marine Sediments of Rhaetian Age. Organic Geochemistry, 20(1): 91–104. https://doi.org/10.1016/0146-6380(93)90084-O |
| Tomašových, A., Siblík, M., 2007. Evaluating Compositional Turnover of Brachiopod Communities during the End-Triassic Mass Extinction (Northern Calcareous Alps): Removal of Dominant Groups, Recovery and Community Reassembly. Palaeogeography, Palaeoclimatology, Palaeoecology, 244(1/2/3/4): 170–200. https://doi.org/10.1016/j.palaeo.2006.06.028 |
| Ullmann, C. V., Szȕcs, D., Jiang, M. J., et al., 2022. Geochemistry of Macrofossil, Bulk Rock and Secondary Calcite in the Early Jurassic Strata of the Llanbedr (Mochras Farm) Drill Core, Cardigan Bay Basin, Wales, UK. Journal of the Geological Society, 179: jgs2021–jgs2018. https://doi.org/10.1144/jgs2021-018 |
| van de Schootbrugge, B., Payne, J. L., Tomasovych, A., et al., 2008. Carbon Cycle Perturbation and Stabilization in the Wake of the Triassic-Jurassic Boundary Mass-Extinction Event. Geochemistry, Geophysics, Geosystems, 9(4): 2007GC001914. https://doi.org/10.1029/2007gc001914 |
| Warrington, G., Cope, J. C. W., Ivimey-Cook, H. C., 1994. St Audrie's Bay, Somerset, England: A Candidate Global Stratotype Section and Point for the Base of the Jurassic System. Geological Magazine, 131(2): 191–200. https://doi.org/10.1017/s0016756800010724 |
| Warrington, G., Wilson, A. A., Jones, N. S., et al., 1996. Chapter 2: Stratigraphy and Sedimentology. In: Plant, J. A., Jones, D. G., Haslam, H. W., eds., Basin Evolution, Fluid Movement and Mineral Resources in a Permo-Triassic Rift Setting: The Cheshire Basin. British Geological Survey, Technical Report, Abingdon |
| Weedon, G. P., Jenkyns, H. C., Page, K. N., 2018. Combined Sea-Level and Climate Controls on Limestone Formation, Hiatuses and Ammonite Preservation in the Blue Lias Formation, South Britain (Uppermost Triassic–Lower Jurassic). Geological Magazine, 155(5): 1117–1149. https://doi.org/10.1017/s001675681600128x |
| Weedon, G. P., Page, K. N., Jenkyns, H. C., 2019. Cyclostratigraphy, Stratigraphic Gaps and the Duration of the Hettangian Stage (Jurassic): Insights from the Blue Lias Formation of Southern Britain. Geological Magazine, 156(9): 1469–1509. https://doi.org/10.1017/s0016756818000808 |
| Whiteside, J. H., Olsen, P. E., Eglinton, T., et al., 2010. Compound-Specific Carbon Isotopes from Earth's Largest Flood Basalt Eruptions Directly Linked to the End-Triassic Mass Extinction. Proceedings of the National Academy of Sciences of the United States of America, 107(15): 6721–6725. https://doi.org/10.1073/pnas.1001706107 |
| Wignall, P. B., Atkinson, J. W., 2020. A Two-Phase End-Triassic Mass Extinction. Earth-Science Reviews, 208: 103282. https://doi.org/10.1016/j.earscirev.2020.103282 |
| Williford, K. H., Ward, P. D., Garrison, G. H., et al., 2007. An Extended Organic Carbon-Isotope Record across the Triassic-Jurassic Boundary in the Queen Charlotte Islands, British Columbia, Canada. Palaeogeography, Palaeoclimatology, Palaeoecology, 244(1/2/3/4): 290–296. https://doi.org/10.1016/j.palaeo.2006.06.032 |
| Wilson, A. A., 1993. The Mercia Mudstone Group (Trias) of the Cheshire Basin. Proceedings of the Yorkshire Geological Society, 49(3): 171–188. https://doi.org/10.1144/pygs.49.3.171 |
| Xu, W. M., Ruhl, M., Hesselbo, S. P., et al., 2017. Orbital Pacing of the Early Jurassic Carbon Cycle, Black-Shale Formation and Seabed Methane Seepage. Sedimentology, 64(1): 127–149. https://doi.org/10.1111/sed.12329 |
| Xu, W. M., Ruhl, M., Jenkyns, H. C., et al., 2018. Evolution of the Toarcian (Early Jurassic) Carbon-Cycle and Global Climatic Controls on Local Sedimentary Processes (Cardigan Bay Basin, UK). Earth and Planetary Science Letters, 484: 396–411. https://doi.org/10.1016/j.epsl.2017.12.037 |
| Yager, J. A., West, A. J., Corsetti, F. A., et al., 2017. Duration of and Decoupling between Carbon Isotope Excursions during the End-Triassic Mass Extinction and Central Atlantic Magmatic Province Emplacement. Earth and Planetary Science Letters, 473: 227–236. https://doi.org/10.1016/j.epsl.2017.05.031 |